Project Summary/Abstract Scientists who are women, disabled or certain racial minorities remain under-represented among the tenure- track faculty at US research universities. Broadening participation by researchers from these under-represented groups (URGs) is a priority, because it will enhance science innovation and productivity, improve future trainees? learning environments and enhance the international competitiveness of the US biomedical enterprise. Recent studies have shown that the postdoc-to-faculty transition is a major attrition point for scientists from URGs on the path to tenure. Therefore, new interventions are needed to support researchers from URGs as they seek and commence tenure-track positions at research-intensive universities. The American Society for Cell Biology (ASCB) is well-positioned to address this need. ASCB has a successful, decades-long history of promoting the research and professional development of scientists from URGs at all career stages. Building on this deep experience and the rich resources of ASCB membership, we propose an ASCB MOSAIC Program (AMP) to enhance the success of scholars from URGs in tenure-track faculty positions. AMP adopts the tripartite integration model of social influence, an established framework postulating that trainees? senses of science efficacy, science identity and alignment of values contribute to their persistence in STEM fields. AMP will provide a combination of evidence-based, rigorously evaluated skills development workshops, mentor training and institutional culture-change initiatives to augment AMP scholars? science efficacy, identity and values alignment. We will accomplish this goal through three Specific Aims: Specific Aim 1: To provide skills development for AMP scholars. We will create a cohort-based professional skills development program that builds on the strengths of AMP scholars to enhance their preparation, hiring, retention and success in tenure-track, research-intensive faculty positions. Specific Aim 2: To train AMP program mentors. We will create a cohort-based training program for AMP scholars? postdoctoral supervisors, plus additional, supplemental scientific and professional development mentors, with these relationships continuing across the postdoc-to-faculty transition. Specific Aim 3: To catalyze institutional interventions that broaden participation among research faculty. We will convene departmental and university leadership to exchange best practices for effecting institutional change, improving their cultures of inclusiveness and broadening participation, retention and success among faculty from URGs. We expect that AMP will significantly enhance our scholars? success as tenure-track research faculty. Our mentor training and institutional change initiatives will also benefit additional trainees and universities, beyond our direct participants, extending AMP?s impact across the nation. We anticipate that the successful completion of AMP will meaningfully advance inclusive excellence across the US academic biomedical workforce.